Change in systemic hemodynamics after acute administration of diazepam binding inhibitor (DBI) and after autoimmunization against DBI

Endogenous peptide DBI inhibits the activity of HABA-ergic system and that is why can be a factor of arterial hypertension development. We investigated DBI influence on cardiac index (CI), arterial pressure (AP) and heart rate (HR) in rats. I.v. administration of DBI caused dose--dependent increase in CI, AP but HR did not change. High dose (150 mg/kg) caused a biphasic answer: hyperkinetic reaction reversed to cardiodepressive one. Long-term immunization against DBI led to decrease of AP and systemic vessel's resistance.